Disposable article having sensor to detect impending elimination of bodily waste

ABSTRACT

A disposable article to be fitted to a wearer having an external anal sphincter muscle, the external anal sphincter muscle having a basal electrical activity. The disposable article preferably comprises a sensor or sensor system operatively connected to the article wherein the sensor is adapted to detect changes in the electrical activity of the wearer&#39;s external anal sphincter muscle that correlates to an impending elimination of bodily waste and to provide a signal to the wearer, a caregiver or an element of the article notifying the wearer, caregiver or element of the article of the impending event.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of prior application U.S.Ser. No. 09/107,561, filed Jun. 29, 1998, issued as U.S. Pat. No.6,149,636, Nov. 21, 2000, which is a continuation in part of priorapplication U.S. Ser. No. 09/106,225, filed Jun. 29, 1998, issued asU.S. Pat. No. 6,186,991, Feb. 13, 2001, and a non-provisional filing ofprior provisional application 60/090,993 filed Jun. 29, 1998.

FIELD OF THE INVENTION

The present invention relates to disposable articles and, moreparticularly, to disposable articles having a sensor adapted to detectan input that correlates to an impending elimination of bodily waste andto provide a signal to the wearer of the article of such impendingevent.

BACKGROUND OF THE INVENTION

Today, disposable articles, such as diapers, pants-type diapers,training pants, adult incontinence briefs, sanitary napkins and tampons,are widely used in infant and toddler care and in the care ofincontinent adults as a means of containing, isolating and disposing ofbodily wastes. These articles have generally replaced reusable, washablecloth garments as the preferred means for these applications because oftheir convenience and reliability. The disposable articles respond to adefecation, urination or discharge event by absorbing or containingbodily wastes deposited on the article. Some disposable articles alsosignal a defecation, urination or discharge event after it has occurred(e.g., wetness indicators, temperature change detection). The articles,however, do not predict when an event is about to occur and prepare thearticle, wearer or caregiver for the occurrence of the predicted event.Current disposable articles have absorbent material in a configurationready for use at the time of application to the wearer or have aconfiguration that does not become available until the time of adischarge of bodily waste or shortly thereafter. Barrier cuffs, forexample, are in position when the article is applied to the wearer.Signaling devices such as thermal or visual indicators signal aurination event only after the urination has begun. For example, knownpotty training devices, however, detect and signal the wearer once thedefecation or urination has begun and do not give the wearer the abilityto get to the bathroom in time to prevent an accident.

SUMMARY OF THE INVENTION

The present invention is directed to a disposable article to be fittedto a wearer having an external anal sphincter muscle, the external analsphincter muscle having a basal electrical activity. The disposablearticle preferably comprises a sensor or sensor system operativelyconnected to the article wherein the sensor is adapted to detect changesin the electrical activity of the wearer's external anal sphinctermuscle that correlates to an impending elimination of bodily waste andto provide a signal to the wearer, a caregiver or an element of thearticle notifying the wearer, caregiver or element of the article of theimpending event.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an article made in accordance with the presentinvention in a flat-out state with portions of the structure beingcut-away to more clearly show the construction of the article, whereinthe article is a diaper.

FIG. 2 shows a perspective view of a bodily waste isolation device ofthe present invention in a compressed state before activation.

FIG. 2A shows a sectional view taken along line 2A—2A of FIG. 2.

FIG. 3A shows a block diagram of an exemplary open loop responsivesystem.

FIG. 3B shows a block diagram of an exemplary closed loop responsivesystem.

FIG. 3C shows a block diagram of an exemplary open loop responsivesystem including a controller.

FIG. 3D shows a block diagram of an exemplary closed loop responsivesystem including a controller.

FIG. 4A shows an ideal output function of a discontinuous responsivesystem of the present invention having a single threshold level.

FIG. 4B shows an ideal output function of a discontinuous responsivesystem of the present invention having multiple threshold levels.

FIG. 5A shows an exemplary output function of a discontinuous responsivesystem of the present invention along with the first, second and thirdderivatives of the output function.

FIG. 5B shows a transfer function of a control system having a series offirst order lags having an equal time constant.

FIGS. 6A and 6B show an embodiment of a responsive system of the presentinvention including an electrically sensitive gel.

FIGS. 7A, 7B and 7C show another embodiment of a responsive system ofthe present invention including an electrically sensitive gel.

FIG. 8 is a perspective view of a waste bag embodiment of the presentinvention.

FIG. 9 is a perspective view of one embodiment of a diaper whichincludes a waste bag.

FIG. 10a is a graphical example of an increase in the basal electricalactivity of an external anal sphincter muscle related to defecation.

FIG. 10b is an graphical example of a decrease in the basal electricalactivity of an external anal sphincter muscle related to defecation.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “absorbent article” refers to devices whichabsorb and contain body exudates, and more specifically, refers todevices which are placed against or in proximity to the body of thewearer to absorb and contain the various exudates discharged from thebody. The term “disposable” is used herein to describe absorbentarticles which generally are not intended to be laundered or otherwiserestored or reused as an absorbent article (i.e., they are intended tobe discarded after a single use and, preferably, to be recycled,composted or otherwise disposed of in an environmentally compatiblemanner). (As used herein, the term “disposed” is used to mean that anelement(s) of the diaper is formed (joined and positioned) in aparticular place or position as a unitary structure with other elementsof the diaper or as a separate element joined to another element of thediaper. As used herein, the term “joined” encompasses configurationswhereby an element is directly secured to another element by affixingthe element directly to the other element, and configurations whereby anelement is indirectly secured to another element by affixing the elementto intermediate member(s) which in turn are affixed to the otherelement.) A “unitary” absorbent article refers to absorbent articleswhich are formed of separate parts united together to form a coordinatedentity so that they do not require separate manipulative parts like aseparate holder and liner. A preferred embodiment of an absorbentarticle of the present invention is a unitary disposable absorbentarticle, such as the diaper 20 shown in FIG. 1. As used herein, the term“diaper” refers to an absorbent article generally worn by infants andincontinent persons about the lower torso. The present invention is alsoapplicable to other absorbent or non-absorbent articles such asincontinence briefs, incontinence undergarments, absorbent inserts,diaper holders and liners, colostomy bags for a natural or artificialanus, feminine hygiene garments, tampons, wipes, disposable towels,tissues, water absorbing articles, oil absorbing articles, spill cleanupbags, desiccant bags, disposable mops, bandages, therapeutic wraps,supports, disposable heating pads and the like.

FIG. 1 is a plan view of the diaper 20 of the present invention in aflat-out, state with portions of the structure being cut-away to moreclearly show the construction of the diaper 20. The portion of thediaper 20 which faces the wearer is oriented towards the viewer. Asshown in FIG. 1, the diaper 20 preferably comprises a liquid pervioustopsheet 24; a liquid impervious backsheet 26; an absorbent core 28,which is preferably positioned between at least a portion of thetopsheet 24 and the backsheet 26; side panels 30; elasticized leg cuffs32; an elastic waist feature 34; and a fastening system generallydesignated 40. Diaper 20 is shown in FIG. 1 to have a first waist region36, a second waist region 38 opposed to the first waist region 36 and acrotch region 37 located between the first waist region and the secondwaist region. The periphery of the diaper 20 is defined by the outeredges of the diaper 20 in which the longitudinal edges 50 run generallyparallel to the longitudinal centerline 100 of the diaper 20 and the endedges 52 run between the longitudinal edges 50 generally parallel to thelateral centerline 110 of the diaper 20.

The chassis 22 of the diaper 20 comprises the main body of the diaper20. The chassis 22 comprises at least a portion of the absorbent core 28and preferably an outer covering layer including the topsheet 24 and thebacksheet 26. If the absorbent article comprises a separate holder and aliner, the chassis 22 generally comprises the holder and the liner. (Forexample, the holder may comprise one or more layers of material to formthe outer cover of the article and the liner may comprise an absorbentassembly including a topsheet, a backsheet, and an absorbent core. Insuch cases, the holder and/or the liner may include a fastening elementwhich is used to hold the liner in place throughout the time of use.)For unitary absorbent articles, the chassis 22 comprises the mainstructure of the diaper with other features added to form the compositediaper structure. While the topsheet 24, the backsheet 26, and theabsorbent core 26 may be assembled in a variety of well knownconfigurations, preferred diaper configurations are described generallyin U.S. Pat. No. 3,860,003 entitled “Contractible Side Portions forDisposable Diaper” which issued to Kenneth B. Buell on Jan. 14, 1975;U.S. Pat. No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat.No. 5,221,274 issued to Buell on Jun. 22, 1993; and U.S. Pat. No.5,554,145 entitled “Absorbent Article With Multiple Zone StructuralElastic-Like Film Web Extensible Waist Feature” which issued to Roe etal. on Sep. 10, 1996; U.S. Pat. No. 5,569,234 entitled “DisposablePull-On Pant” which issued to Buell et al. on Oct. 29, 1996; U.S Pat.No. 5,580,411 entitled “Zero Scrap Method For Manufacturing Side PanelsFor Absorbent Articles” which issued to Nease et al. on Dec. 3, 1996;and U.S. patent application Ser. No. 08/915,471 entitled “AbsorbentArticle With Multi-Directional Extensible Side Panels” filed Aug. 20,1997 in the name of Robles et al.; each of which is incorporated hereinby reference.

The backsheet 26 is generally that portion of the diaper 20 positionedadjacent the garment facing surface 45 of the absorbent core 28 whichprevents the exudates absorbed and contained therein from soilingarticles which may contact the diaper 20, such as bedsheets andundergarments. In preferred embodiments, the backsheet 26 is imperviousto liquids (e.g., urine) and comprises a thin plastic film such as athermoplastic film having a thickness of about 0.012 mm (0.5 mil) toabout 0.051 mm (2.0 mils). Suitable backsheelt films include thosemanufactured by Tredegar Industries Inc. of Terre Haute, Ind. and soldunder the trade names X15306, X10962 and X10964. Other suitablebacksheet materials may include breathable materials which permit vaporsto escape from the diaper 20 while still preventing exudates frompassing through the backsheet 26. Exemplary breathable materials mayinclude materials such as woven webs, nonwoven webs, composite materialssuch as film-coated nonwoven webs, and microporous films such asmanufactured by Mitsui Toatsu Co., of Japan under the designation ESPOIRNO and by EXXON Chemical Co., of Bay City, Tex., under the designationEXXAIRE. Suitable breathable composite materials comprising polymerblends are available from Clopay Corporation, Cincinnati, Ohio under thename HYTREL blend P18-3097. Such breathable composite materials aredescribed in greater detail in PCT Application No. WO 95/16746,published on Jun. 22, 1995 in the name of E. I. DuPont and copendingU.S. Pat. No. 5,865,823 issued to Curro on Feb. 2, 1999. Otherbreathable backsheets including nonwoven webs and apertured formed filmsare described in U.S. Pat. No. 5,571,096 issued to Dobrin et al. on Nov.5, 1996. Each of these references is hereby incorporated by referenceherein.

The backsheet 26, or any portion thereof, may be elastically extensiblein one or more directions. In one embodiment, the backsheet 26 maycomprise a structural elastic-like film (“SELF”) web. A structuralelastic-like film web is an extensible material that exhibits anelastic-like behavior in the direction of elongation without the use ofadded elastic materials. SELF webs suitable for the present inventionare more completely described in U.S. Pat. No. 5,518,801 entitled WebMaterials Exhibiting Elastic-Like Behavior, which issued to Chappell,et, al. on May 21, 1996, which is incorporated herein by reference. Inalternate embodiments, the backsheet 26 may comprise elastomeric films,foams, strands, or combinations of these or other suitable materialswith nonwovens or synthetic films.

The backsheet 26 may be joined to the topsheet 24, the absorbent core 28or any other element of the diaper 20 by any attachment means known inthe art. For example, the attachment means may include a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. One preferredattachment means comprises an open pattern network of filaments ofadhesive as disclosed in U.S. Pat. No. 4,573,986 entitled “DisposableWaste-Containment Garment”, which issued to Minetola et al. on Mar. 4,1986. Other suitable attachment means include several lines of adhesivefilaments which are swirled into a spiral pattern, as is illustrated bythe apparatus and methods shown in U.S. Pat. No. 3,911,173 issued toSprague, Jr. on Oct. 7, 1975; U.S. Pat. No. 4,785,996 issued to Ziecker,et al. on Nov. 22, 1978; and U.S. Pat. No. 4,842,666 issued to Wereniczon Jun. 27, 1989. Each of these patents are incorporated herein byreference. Adhesives which have been found to be satisfactory aremanufactured by H. B. Fuller Company of St. Paul, Minn. and marketed asHL-1620 and HL-1358-XZP. Alternatively, the attachment means maycomprise heat bonds, pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as are known in the art.

The topsheet 24 is preferably positioned adjacent the body surface 47 ofthe absorbent core 28 and may be joined thereto and/or to the backsheet26 by any attachment means known in the art. Suitable attachment meansare described above with respect to means for joining the backsheet 26to other elements of the diaper 20. In one preferred embodiment of thepresent invention, the topsheet 24 and the backsheet 26 are joineddirectly to each other in some locations and are indirectly joinedtogether in other locations by directly joining them to other elementsof the diaper 20.

The topsheet 24 is preferably compliant, soft feeling, andnon-irritating to the wearer's skin. Further, at least a portion of thetopsheet 24 is liquid pervious, permitting liquids to readily penetratethrough its thickness. A suitable topsheet 24 may be manufactured from awide range of materials, such as porous foams; reticulated foams;apertured plastic films; or woven or nonwoven webs of natural fibers(e.g., wood or cotton fibers), synthetic fibers (e.g., polyester orpolypropylene fibers), or a combination of natural and synthetic fibers.If the topsheets include fibers, the fibers may be spunbond, carded,wet-laid, meltblown, hydroentangled, or otherwise processed as is knownin the art. One suitable topsheet 24 comprising a web of staple lengthpolypropylene fibers is manufactured by Veratec, Inc., a Division ofInternational Paper Company, of Walpole, Mass. under the designationP-8.

Suitable formed film topsheets are described in U.S. Pat. No. 3,929,135,entitled “Absorptive Structures Having Tapered Capillaries”, whichissued to Thompson on Dec. 30, 1975; U.S. Pat. No. 4,324,246 entitled“Disposable Absorbent Article Having A Stain Resistant Topsheet”, whichissued to Mullane, et al. on Apr. 13, 1982; U.S. Pat. No. 4,342,314entitled “Resilient Plastic Web Exhibiting Fiber-Like Properties”, whichissued to Radel, et al. on Aug. 3, 1982; U.S. Pat. No. 4,463,045entitled “Macroscopically Expanded Three-Dimensional Plastic WebExhibiting Non-Glossy Visible Surface and Cloth-Like TactileImpression”, which issued to Ahr, et al. on Jul. 31, 1984; and U.S. Pat.No. 5,006,394 “Multilayer Polymeric Film” issued to Baird on Apr. 9,1991. Other suitable topsheets 30 are made in accordance with U.S. Pat.Nos. 4,609,518 and 4,629,643 which issued to Curro et al. on Sep. 2,1986 and Dec. 16, 1986, respectively, and both of which are incorporatedherein by reference. Such formed films are available from The Procter &Gamble Company of Cincinnati, Ohio as “DRI-WEAVE” and from TredegarCorporation of Terre Haute, Ind. as “CLIFF-T.”

Preferably, the topsheet 24 is made of a hydrophobic material or istreated to be hydrophobic in order to isolate the wearer's skin fromliquids contained in the absorbent core 28. If the topsheet 24 is madeof a hydrophobic material, preferably at least the upper surface of thetopsheet 24 is treated to be hydrophilic so that liquids will transferthrough the topsheet more rapidly. This diminishes the likelihood thatbody exudates will flow off the topsheet 24 rather than being drawnthrough the topsheet 24 and being absorbed by the absorbent core 28. Thetopsheet 24 can be rendered hydrophilic by treating it with a surfactantor by incorporating a surfactant into the topsheet. Suitable methods fortreating the topsheet 24 with a surfactant include spraying the topsheet24 material with the surfactant and immersing the material into thesurfactant. A more detailed discussion of such a treatment andhydrophilicity is contained in U.S. Pat. No. 4,988,344 entitled“Absorbent Articles with Multiple Layer Absorbent Layers” issued toReising, et al. on Jan. 29, 1991 and U.S. Pat. No. 4,988,345 entitled“Absorbent Articles with Rapid Acquiring Absorbent Cores” issued toReising on Jan. 29, 1991. A more detailed discussion of some suitablemethods for incorporating surfactant in the topsheet can be found inU.S. Statutory Invention Registration No. HI670, published on Jul. 1,1997 in the names of Aziz et al. Each of these references is herebyincorporated by reference herein. Alternatively, the topsheet 24 mayinclude an apertured web or film which is hydrophobic. This may beaccomplished eliminating the hydrophilizing treatment step from theproduction process and/or applying a hydrophobic treatment to thetopsheet 24, such as a polytetraflouroethylene compound like SCOTCHGUARDor a hydrophobic lotion composition, as described below. In suchembodiments, it is preferred that the apertures be large enough to allowthe penetration of aqueous fluids like urine without significantresistance.

Any portion of the topsheet 24 may be coated with a lotion as is knownin the art. Examples of suitable lotions include those described in U.S.Pat. No. 5,607,760 entitled “Disposable Absorbent Article Having ALotioned Topsheet Containing an Emollient and a Polyol PolyesterImmobilizing Agent” which issued to Roe on Mar. 4, 1997, U.S. Pat. No.5,609,587 entitled “Diaper Having A Lotion Topsheet Comprising A LiquidPolyol Polyester Emollient And An Immobilizing Agent” which issued toRoe on Mar. 11, 1997; U.S. Pat. No. 5,635,191 entitled “Diaper Having ALotioned Topsheet Containing A Polysiloxane Emollient” which issued toRoe et al. on Jun. 3, 1997; and U.S. Pat. No. 5,643,588 entitled “DiaperHaving A Lotioned Topsheet” which issued to Roe et al. on Jul. 1, 1997.The lotion may function alone or in combination with another agent asthe hydrophobizing treatment described above. The topsheet may alsoinclude or be treated with antibacterial agents, some examples of whichare disclosed in PCT Publication No. WO 95/24173 entitled “AbsorbentArticles Containing Antibacterial Agents in the Topsheet For OdorControl” which was published on Sep. 14, 1995 in the name of TheresaJohnson. Further, the topsheet 24, the backsheet 26 or any portion ofthe topsheet or backsheet may be embossed and/or matte finished toprovide a more cloth like appearance.

The absorbent core 28 may comprise any absorbent material which isgenerally compressible, conformable, non-irritating to the wearer'sskin, and capable of absorbing and retaining liquids such as urine andother certain body exudates. The absorbent core 28 may be manufacturedin a wide variety of sizes and shapes (e.g., rectangular, hourglass,“T”-shaped, asymmetric, etc.) and may comprise a wide variety ofliquid-absorbent materials commonly used in disposable diapers and otherabsorbent articles such as comminuted wood pulp, which is generallyreferred to as airfelt. Examples of other suitable absorbent materialsinclude creped cellulose wadding; meltblown polymers, including coform;chemically stiffened, modified or cross-linked cellulosic fibers;tissue, including tissue wraps and tissue laminates; absorbent foams;absorbent sponges; superabsorbent polymers; absorbent gelling materials;or any other known absorbent material or combinations of materials.

The configuration and construction of the absorbent core 28 may also bevaried (e.g., the absorbent core(s) or other absorbent structure(s) mayhave varying caliper zones, a hydrophilic gradient, a superabsorbentgradient, or lower average density and lower average basis weightacquisition zones; or may comprise one or more layers or structures).However, the total absorbent capacity of the absorbent core 28 should becompatible with the design loading and the intended use of the diaper20.

Exemplary absorbent structures for use as the absorbent assemblies aredescribed in U.S. Pat. No. 4,610,678 entitled “High-Density AbsorbentStructures” issued to Weisman et al. on Sep. 9, 1986; U.S. Pat. No.4,673,402 entitled “Absorbent Articles With Dual-Layered Cores” issuedto Weisman et al. on Jun. 16, 1987; U.S. Pat. No. 4,834,735, entitled“High Density Absorbent Members Having Lower Density and Lower BasisWeight Acquisition Zones”, issued to Alemany et al. on May 30, 1989;U.S. Pat. No. 4,888,231 entitled “Absorbent Core Having A Dusting Layer”issued to Angstadt on Dec. 19, 1989; U.S. Pat. No. 5,137,537 entitled“Absorbent Structure Containing Individualized, Polycarboxylic AcidCrosslinked Wood Pulp Cellulose Fibers” which issued to Herron et al. onAug. 11, 1992; U.S. Pat. No. 5,147,345 entitled “High EfficiencyAbsorbent Articles For Incontinence Management” issued to Young et al.on Sep. 15, 1992; U.S. Pat. No. 5,342,338 entitled “Disposable AbsorbentArticle For Low-Viscosity Fecal Material” issued to Roe on Aug. 30,1994; U.S. Pat. No. 5,260,345 entitled “Absorbent Foam Materials ForAqueous Body Fluids and Absorbent Articles Containing Such Materials”issued to DesMarais et al. on Nov. 9, 1993; U.S. Pat. No. 5,387,207entitled “Thin-Until-Wet Absorbent Foam Materials For Aqueous BodyFluids And Process For Making Same” issued to Dyer et al. on Feb. 7,1995; and U.S. Pat. No. 5,625,222 entitled “Absorbent Foam Materials ForAqueous Fluids Made From high Internal Phase Emulsions Having Very HighWater-To-Oil Ratios” issued to DesMarais et al. on Jul. 22, 1997. Eachof these patents is incorporated herein by reference.

The diaper 20 may also comprise at least one elastic waist feature 34that helps to provide improved fit and containment. The elastic waistfeature 34 is generally intended to elastically expand and contract todynamically fit the wearer's waist. The elastic waist feature 34preferably extends at least longitudinally outwardly from at least onewaist edge 62 of the absorbent core 28 and generally forms at least aportion of the end edge 52 of the diaper 20. Disposable diapers areoften constructed so as to have two elastic waist features, onepositioned in the first waist region 36 and one positioned in the secondwaist region 38. Further, while the elastic waist feature 34 or any ofits constituent elements may comprise one or more separate elementsaffixed to the diaper 20, the elastic waist feature 34 may beconstructed as an extension of other elements of the diaper 20, such asthe backsheet 26, the topsheet 24, or both the backsheet 26 and thetopsheet 24.

The elastic waist feature 34 may be constructed in a number of differentconfigurations including those described in U.S. Pat. No. 4,515,595issued to Kievit et al. on May 7, 1985; U.S. Pat. No. 4,710,189 issuedto Lash on Dec. 1, 1987; U.S. Pat. No. 5,151,092 issued to Buell on Sep.9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22, 1993.Other suitable waist configurations may include waistcap features suchas those described in U.S. Pat. No. 5,026,364 issued to Robertson onJun. 25, 1991 and U.S. Pat. No. 4,816,025 issued to Foreman on Mar. 28,1989. All of the above mentioned references are incorporated herein byreference.

The diaper 20 may also include a fastening system 40. The fasteningsystem 40 preferably maintains the first waist region 36 and the secondwaist region 38 in an overlapping configuration so as to provide lateraltensions about the circumference of the diaper 20 to hold the diaper 20on the wearer. The fastening system 40 preferably comprises tape tabsand/or hook and loop fastening components, although any other knownfastening means are generally acceptable. Some exemplary fasteningsystems are disclosed in U.S. Pat. No. 3,848,594 entitled “TapeFastening System for Disposable Diaper” issued to Buell on Nov. 19,1974; U.S. Pat. No. 4,662,875 entitled “Absorbent Article” issued toHirotsu et al. on May 5, 1987; U.S. Pat. No. 4,846,815 entitled“Disposable Diaper Having An Improved Fastening Device” issued toScripps on Jul. 11, 1989; U.S. Pat. No. 4,894,060 entitled “DisposableDiaper With Improved Hook Fastener Portion” issued to Nestegard on Jan.16, 1990; U.S. Pat. No. 4,946,527 entitled “Pressure-Sensitive AdhesiveFastener And Method of Making Same” issued to Battrell on Aug. 7, 1990;and the herein before referenced U.S. Pat. No. 5,151,092 issued to Buellon Sep. 9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22,1993. The fastening system may also provide a means for holding thearticle in a disposal configuration as disclosed in U.S. Pat. No.4,963,140 issued to Robertson et al. on Oct. 16, 1990. Each of thesepatents is incorporated herein by reference. In alternative embodiments,opposing sides of the garment may be seamed or welded to form a pant.This allows the article to be used as a pull-on type diaper, such as atraining pant.

The diaper 20 may also comprise side panels 30. The side panels 30 maybe elastic or extensible to provide a more comfortable and contouringfit by initially conformably fitting the diaper 20 to the wearer andsustaining this fit throughout the time of wear well past when thediaper 20 has been loaded with exudates since the elasticized sidepanels 30 allow the sides of the diaper 20 to expand and contract. Theside panels 30 may also provide more effective application of the diaper20 because even if the diaperer pulls one elasticized side panel 30farther than the other during application, the diaper 20 will“self-adjust” during wear.

While the diaper 20 of the present invention preferably has the sidepanels 30 disposed in the second waist region 38, the diaper 20 may beprovided with side panels 30 disposed in the first waist region 36 or inboth the first waist region 36 and the second waist region 38. The sidepanels 30 may be constructed in any suitable configurations. Examples ofdiapers with elasticized side panels are disclosed in U.S. Pat. No.4,857,067, entitled “Disposable Diaper Having Shirred Ears” issued toWood, et al. on Aug 15, 1989; U.S. Pat. No. 4,381,781 issued toSciaraffa, et al. on May 3, 1983; U.S. Pat. No. 4,938,753 issued to VanGompel, et al. on Jul. 3, 1990; the herein before referenced U.S. Pat.No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat. No.5,221,274 issued to Buell on Jun. 22, 1993; U.S. Pat. No. 5,669,897issued to LaVon, et al. on Sep. 23, 1997 entitled “Absorbent ArticlesProviding Sustained Dynamic Fit”; U.S. patent application Ser. No.08/915,471 entitled “Absorbent Article With Multi-Directional ExtensibleSide Panels” filed Aug. 20, 1997 in the names of Robles, et al.; each ofwhich is incorporated herein by reference.

The diaper 20 preferably further includes leg cuffs 32 which provideimproved containment of liquids and other body exudates. Leg cuffs mayalso be referred to as leg bands, side flaps, barrier cuffs, or elasticcuffs. U.S. Pat. No. 3,860,003 describes a disposable diaper whichprovides a contractible leg opening having a side flap and one or moreelastic members to provide an elasticized leg cuff (a gasketing cuff).U.S. Pat. Nos. 4,808,178 and 4,909,803 issued to Aziz et al. on Feb. 28,1989 and Mar. 20, 1990, respectively, describe disposable diapers having“stand-up” elasticized flaps (barrier cuffs) which improve thecontainment of the leg regions. U.S. Pat. Nos. 4,695,278 and 4,795,454issued to Lawson on Sep. 22, 1987 and to Dragoo on Jan. 3, 1989,respectively, describe disposable diapers having dual cuffs, includinggasketing cuffs and barrier cuffs. In some embodiments, it may bedesirable to treat all or a portion of the leg cuffs with a lotion, asdescribed above.

Embodiments of the present invention may also include pockets forreceiving and containing waste, spacers which provide voids for waste,barriers for limiting the movement of waste in the article, compartmentsor voids which accept and contain waste materials deposited in thediaper, and the like, or any combinations thereof. Examples of pocketsand spacers for use in absorbent products are described in U.S. Pat. No.5,514,121 issued to Roe et al. on May 7, 1996, entitled “Diaper HavingExpulsive Spacer”; U.S. Pat. No. 5,171,236 issued to Dreier et al onDec. 15, 1992, entitled “Disposable Absorbent Article Having CoreSpacers”; U.S. Pat. No. 5,397,318 issued to Dreier on Mar. 14, 1995,entitled “Absorbent Article Having A Pocket Cuff”; U.S. Pat. No.5,540,671 issued to Dreier on Jul. 30, 1996, entitled “Absorbent ArticleHaving A Pocket Cuff With An Apex”; and PCT Application WO 93/25172published Dec. 3, 1993, entitled “Spacers For Use In Hygienic AbsorbentArticles And Disposable Absorbent Articles Having Such Spacer”; and U.S.Pat. No. 5,306,266, entitled “Flexible Spacers For Use In DisposableAbsorbent Articles”, issued to Freeland on Apr. 26, 1994. Examples ofcompartments or voids are disclosed in U.S. Pat. No. 4,968,312, entitled“Disposable Fecal Compartmenting Diaper”, issued to Khan on Nov. 6.,1990; U.S. Pat. No. 4,990,147, entitled “Absorbent Article With ElasticLiner For Waste Material Isolation”, issued to Freeland on Feb. 5, 1991;U.S. Pat. No. 5,62,840, entitled “Disposable Diapers”, issued to Holt etal on Nov. 5, 1991; and U.S. Pat. No. 5,269,755 entitled “TrisectionTopsheets For Disposable Absorbent Articles And Disposable AbsorbentArticles Having Such Trisection Topsheets”, issued to Freeland et al onDec. 14, 1993. Examples of suitable transverse barriers are described inU.S. Pat. No. 5,554,142 entitled “Absorbent Article Having MultipleEffective Height Transverse Partition” issued Sep. 10, 1996 in the nameof Dreier et al.; PCT Patent WO 94/14395 entitled “Absorbent ArticleHaving An Upstanding Transverse Partition” published Jul. 7, 1994 minthe name of Freeland, et al.; and U.S. Pat. No. 5,653,703 AbsorbentArticle Having Angular Upstanding Transverse Partition, issued Aug. 5,1997 to Roe, et al. All of the above-cited references are herebyincorporated by reference herein.

Embodiments of the present invention may also include a waste managementdevice 110 such as is shown in FIG. 8. The waste management device 110may include a waste bag 111 to collect feces, urine or both. The wastebag 111 may have an aperture 121 and a flange 112 surrounding theaperture for preferably adhesive attachment to the perianal area of awearer. Further, the waste management device 110 has been found to beparticularly useful and beneficial when used in conjunction with agarment, or diaper, preferably a disposable diaper. One example of adiaper 120 including a waste bag 111 is shown in FIG. 9. If associatedwith a diaper 120 or other garment, the waste bag 111 may be disposed onor joined to any surface of the article. The bag 111 may be joined tothe article by any known means, including any of the joining orattaching means described herein and/or any other joining means such asadhesive, hook and loop fasteners, magnetics, belts, ties, straps,snaps, etc. In one embodiment, the waste bag 111 is joined to thetopsheet 124 of the diaper 120.

The waste bag 111 is preferably a flexible receptacle for thecontainment of excreted fecal matter or urine. Thus, the waste bag 111is preferably liquid impermeable, and yet it may be breathable. Further,the waste bag 111 is designed of sufficient strength to withstandtypical wearing conditions, such as sitting.

The waste bag 111 may comprise one or multiple layers. In oneembodiment, the waste bag 111 may comprise three layers, preferably onefilm and two non-woven layers. The layers of the bag material maycomprise any material, preferably so that the bag is liquid impervious.In a preferred embodiment of the present invention a laminate may beformed from a non-woven layer and a film.

Suitable film materials for any of the film layers preferably comprise athermoplastic material. The thermoplastic material can may be vaporpervious or impervious and can be selected from among all types ofhot-melt adhesives, polyolefins especially polyethylene, polypropylene,amorphous polyolefins, and the like, material containing meltablecomponents comprising fibres or polymeric binders including naturalfibres such as cellulose—wood pulp, cotton, jute, hemp; synthetic fibressuch as fibreglass, rayon, polyester, polyolefin, acrylic, polyamid,aramid, polytetrafluroethylene metal, polyimide; binders such asbicomponent high melt/low melt polymer, copolymer polyester, polyvinylchloride, polyvinyl acetate/chloride copolymer, copolymer polyamide,materials comprising blends wherein some of the constituent materialsare not meltable; air and vapour permeable materials includingmicroporous films such as those described above with respect to thebacksheet and monolithic breathable materials such as HYTREL™ availablefrom DuPont and Pebax™ available from ELF Atochem, France.

The waste bag 111 may have any shape or size. Preferred shapes includeflat circular type bags, cone shaped bags, truncated cone shaped bagsand pyramidal or truncated pyramidal shaped bags and flat T shaped bags.Further, the waste bag 111 may be provided from a unitary piece ofmaterial or a number of separate pieces of material which may beidentical or different and which may be sealed at their respectiveperipheries.

The waste bag 111 may also contain absorbent material. The absorbentmaterial may comprise any absorbent material which is capable ofabsorbing and retaining liquids. The absorbent material may comprise awide variety of liquid-absorbent materials commonly used in disposablediapers and other absorbent articles. Some examples are described hereinwith respect to the absorbent core.

The waste bag 111 is provided with an aperture 121 whereby fecal matteror urine is received from the body prior to storage within the bagcavity. The aperture 121 is preferably surrounded by a flange 112 andmay be provided in any shape or size, such as circular, oblong, heartshaped and may be symmetrical or asymmetrical, preferably the aperturehas an oblong configuration either in the longitudinal or in thetransversal direction. The flange may comprise projections designed tofit the perineal, genital and/or coccygeal area of the wearer.

The flange 112 should be made of soft, flexible and malleable materialto allow easy placement of the flange 112 to the perianal or uro-genitalarea. Typical materials include nonwoven materials, wovens, open celledthermoplastic foams, closed-cell thermoplastic foams, composites of opencelled foams and stretch nonwoven, and films.

The waste bag 111 preferably further comprises a joining or attachmentmeans to secure the device to the wearer. Such means may comprise any ofthe joining or attachment means described herein or any other suitablejoining or fastening means known in the art such as straps, belts, hookand loop fastenters, pins, ties, snaps and/or a body-compatible adhesiveapplied to the wearer facing portion of the waste bag 111 or the flange.Any skin-friendly water resistant pressure sensitive adhesive may beused to attach the device to the perianal or urogenital area of thewearer, such as hydrocolloid adhesives and hydrogel adhesives.Particularly effective adhesives in providing the desired adhesiveproperties to secure the flange to the skin of the wearer at thesensitive perianal area, while allowing for relatively painlessapplication and removal, are formed from crosslinking polymers with aplastisicer to form a 3-dimensional matrix.

The diaper 20 may also comprise one or more “proactive sensors” 60. Asused in this application, the term “proactive sensor” refers to a sensoror sensor system that is capable of detecting or monitoring changes orsignals in or on the body of the wearer, in the article or in the waste,i.e., inputs, that directly relate or, at a minimum, correlate to theoccurrence of an impending event related to the bodily waste, thewearer, the article or a component or components thereof. Proactivesensors may respond to one or more specific inputs. Examples of inputsthat may be detected by a proactive sensor of the present invention inorder to predict an impending event include, but are not limited to,attitude, pressure, motion, vibration, contraction, tension, bloodflow,moisture, temperature, enzymes, bacteria, pH, conductivity, resistance,capacitance, inductance or other chemical, biochemical, biological,mechanical or electrical properties and/or components of bodily wastes.The sensor 60, for example, may be chemical, mechanical, electrical,thermal, etc. A chemical sensor may respond to chemical and/orbiochemical inputs such as enzymes typically present in bodily wastes,pH, water, humidity or moisture, and/or biological inputs such asbacteria, blood or any other components of bodily wastes such as feces,urine, or menses, etc. Examples of chemical or biochemical sensorsinclude dissolving or rupturable films, capsules, cells, seals, etc.that dissolve or rupture in response to a specific chemical, biochemicalor biological input or to a specific class of chemical, biochemical orbiological inputs. A mechanical sensor may also respond to motion,attitude, pressure, etc. An example of a mechanical sensor is abellows-type sensor in which when the pelvic floor drops prior todefecation and the pressure pushes down on the bellows to inflate aportion of the sensor. A mechanical sensor may also include a sensor ora portion of the sensor that is broken or separated under a pre-definedapplied pressure. An electrical sensor may also respond to moisture,urine, feces, menses, pressure, heat, temperature, conductance,resistance, capacitance, inductance, etc. An electrical sensor may, forexample, include a sensor in which a conductive input such as urinecompletes an electrical circuit; a sensor in which an input such aspressure, tension or heat closes an electrical contact to complete acircuit; a piezoelectric sensor that generates a signal via pressureinduced by the wearer or a part of the wearer (e.g., from motion ormuscle tone); a sensor in which the resistance, capacitance orinductance varies in the presence of the input to which the sensorresponds (e.g., conductance of the wearer's skin); or a sensor thatreceives electrical signals from the body (e.g., from the subcutaneousmuscles) of the wearer through a contact such as a skin contact sensor.A thermal sensor may also be used to detect changes in temperature.Optionally, the sensor may be a biosensor as known in the art (e.g., anenzyme sensor, organella sensor, tissue sensor, microorganism sensor, orelectrochemical sensor). The sensor may be adapted to detect proteins,sugars, bile components, etc. such as described in U.S. Pat. No.4,636,474 entitled “Toilet Apparatus,” issued to Kenji Ogura et al. onJan. 13, 1987. Biosensors may comprise bio-recognition systems,typically enzymes or binding proteins such as antibodies immobilizedonto the surface of physico-chemical transducers. The biosensors maydetect components of bodily wastes, such as ammonia and phenol (e.g.,via biosensors comprising enzyme electrodes). A specific strain ofbacteria may be detected via biosensors employing antibodies raisedagainst that bacterial strain. Exemplary enzyme electrodes that may beused to detect phenols (e.g. in urine or feces) include tyrosinase basedelectrodes or polyphenol oxidase enzyme electrodes described in U.S.Pat. No. 5,676,820 entitled “Remote Electrochemical Sensor,” issued toJoseph Wang et al. on Oct. 14, 1997 and U.S. Pat. No. 5,091,299 entitled“An Enzyme Electrode For Use In Organic Solvents,” issued to Anthony P.F. Turner et al. on Feb. 25, 1992, respectively.

Further, a sensor of the present invention may also be reversible orirreversible. A dissolving film or capsule is an example of anirreversible sensor, while an electrical sensor that receives electricalsignals from the body of a wearer may receive multiple signals insuccession.

A proactive sensor 60 may detect an impending event or detect aparameter that directly relates, or at a minimum correlates to theoccurrence of an impending event. An impending event that may bedetected or predicted by a proactive sensor 60 of the present inventionmay include, for example, urination, defecation, heat rash, skinirritation or rash, skin pressure marks, or an illness or medicalcondition of the wearer such as an internal infection (e.g., jaundice),a vitamin deficiency, a bile duct blockage, candidiasis, a parasite, apotential chronic skin condition or irritation, etc. A parameter thatcorrelates to an event is any measurable input, signal such as one ormore of the potential inputs listed above, that correlates with theoccurrence of the event within the frame of reference of the system(i.e., a signal caused by the waste or the wearer). The proactive sensor60 may, for example, predict the occurrence of a defecation, urinationor discharge of bodily waste or may detect signals that may precede skinrash or irritation. Proactive sensors 60 in an article may measure manydifferent inputs in order to predict an event. For example, theproactive sensor 60 may monitor the external anal sphincter muscle for acontraction or relaxation in the anal sphincter that precedes therelease of feces and/or urine, a separation of the buttocks, a pressurechange in the abdomen, a gas concentration in the article, a drop in thepelvic floor, or any other indication that may be used to predict oranticipate the occurrence of an event such as a defecation, a urinationor a discharge of bodily wastes. Alternatively, a proactive sensor 60 ofthe present invention may detect signals that precede skin irritation.For example, the sensor may detect residual fecal contamination of thewearer's skin (e.g., fecal enzyme residue left on the wearer's skinafter cleaning up a soiled diaper) that may, over time, lead toirritated skin. Detection of a high pH, an increased skin hydrationresulting in a measurable increase in conductance or decrease inimpedance of skin, a specific microorganism, fecal enzymes, etc. mayalso be used to predict potential skin irritation.

The proactive sensor 60 may be disposed in and/or operatively connectedto any portion of a disposable article that will be exposed to the inputthat the sensor is designed to detect. For the purposes of the presentinvention, the term “operatively connected” refers to a means ofcommunication such that the proactive sensor 60 may signal some portionof the article 20 when the proactive sensor 60 detects an input. Theproactive sensor 60 may be separate from and operatively connected toanother portion of the proactive sensor 60, another sensor 60, anactuator 70, a controller 80 or some other portion or component of thearticle 20. “Operatively connected” may, for example, include a means ofcommunication such as an electrical connection via a conductive wire ormember, via a transmitted signal such as radio frequency, infrared oranother transmitted frequency communication. Alternatively, the sensor60 may be operatively connected via a mechanical connection such as apneumatic or a hydraulic connection.

In article 20, for example, the proactive sensor 60 may be located inthe front waist region 36, the rear waist region 38 or the crotch region37 of article 20, and may be integral with, disposed adjacent to, joinedto, or comprise a portion of the chassis 22, the topsheet 24, thebacksheet 26, the absorbent core 28, side panels 30, leg cuffs 32, awaist feature 34, a fastening system 40, the longitudinal 50 or end 52edges, etc. The proactive sensor 60 may be integral with the article 20,or may be installed by the caretaker or the wearer. The proactive sensor60 may be completely contained within the article such as article 20 ormay have a receiving portion located in the article such that it willcome into contact with the desired input and another portion such as atransmitting portion located either in the article or outside thearticle. The proactive sensor 60 may be external to the article 20 yetoperatively connected to some portion of the article 20 such that theproactive sensor 60 may detect an input external to the article 20 andprovide a signal to a controller 80 and/or an actuator 70. In someembodiments, the sensor may be separate from the article, e.g.,separately applied to some portion of the wearer, and/or may have one ormore component separate from the article.

The proactive sensor 60 may further comprise a sensing “system”including two or more sensors, each of which may detect the same ordifferent signals from the same or different sources. The sensing systemmay include components that are located inside, external to and/orseparate from the article. For example, the sensing system may include asensor inside the article that detects electrical signals in theexternal anal sphincter of the wearer and a sensor external to thearticle that detects motion, tension or muscle activity in the abdomenof the wearer. The sensing system may also or alternatively includecomponents other than the sensing elements inside, external to and/orseparate from the article. The sensing system, for example, may includea transmitter that is external to the article and transmits a signal toanother part of the sensing system that is joined to or disposed in thearticle 20.

The article 20 preferably also comprises an actuator 70. As used in thisapplication, the term “actuator” refers to a device that comprises“potential” and a means of transforming that potential to perform oractivate a “responsive function.” The potential of the actuator 70 maycomprise either stored or potential energy or stored material. Theactuator 70 thus may perform or activate a responsive function bytransforming potential energy to kinetic energy or by releasing ordelivering a stored material. A “responsive function” is defined for thepurposes of the present invention as a function performed upon thebodily waste, the wearer, the article, or a component or componentsthereof, or a signal to the wearer or the caretaker. A component ofbodily waste may include, for example, moisture, electrolytes, enzymes,volatile gases, bacteria, blood, etc. A component of the wearer may alsoinclude skin, genitalia, the anus, the external anal sphincter muscle,etc. A component of the article may also include leg cuffs, waist cuffsor other waste barriers and/or containment components, side panels,ears, a chassis, an absorbent core, an acquisition component, afastening system, the longitudinal or end edges, etc. Potential energymay be stored as mechanical, electrical, chemical or thermal energy.“kinetic energy” as used in this application refers to the capacity todo work or to perform a responsive function as described above (e.g.,expansion of a compressed device, rotation of a twisted device, a gelthat moves as it changes phases, coating or treatment of skin or feces,inhibition of an enzyme, adjustment of pH, etc.).

Triggering the creation of a three dimensional structure to capturewaste, for example, involves responsive functions performed on acomponent of the article and, ultimately, on the waste. Capturing waste,wiping the skin of the wearer, treating the feces with a feces modifyingagent, or treating the skin with a skin care composition, for example,are responsive functions performed on the waste and/or the wearer.Adjusting the article's geometry (in one, two or three dimensions) orphysical properties (e.g., bending modulus, geometry, etc.) are examplesof responsive functions, which may be performed on the article.Signaling a caretaker and/or the wearer that an event is about to occuris also considered a responsive function for the purposes of the presentinvention. An actuator of a disposable article may, for example, releaseor deliver a deodorant, enzyme inhibitor, skin care composition or pHcontrol agent; capture, wipe, cover, trap, immobilize, seal, pump, orstore bodily waste; or trigger the release or creation of a structure orelement designed to perform one or more of these functions or any otherresponsive function upon the waste, wearer, article, or a componentthereof.

An actuator 70 of the present invention may release potential energy toperform or activate a responsive function upon the waste, the wearer,the article, or a component thereof. The release of potential energy maytransform mechanical, electrical, chemical or thermal potential energyinto mechanical, electrical or chemical kinetic energy to perform theresponsive function. Actuators may be triggered by a threshold level ofan input to release potential energy to perform a responsive function ormay respond continuously to an input as described below. For example, acompressed foam has stored compressive mechanical potential energy andmay provide mechanical kinetic energy when it is released. A twistedfoam has stored torsional mechanical potential energy that may providemechanical kinetic energy, i.e., rotation, when it is released. Inaddition, stored chemical, electrical or thermal energy may be used torelease electrical, mechanical, chemical or thermal kinetic energy. Anactuator of a disposable article, for example, may include one or moreof the following: stored lotion, feces modification agents, enzymeinhibitors, pH buffers, dyes, pressurized gas, a compressed foam, atwisted foam, a pump, a closed system liquid transport member, anelectrically sensitive gel, a pH sensitive gel, a salt concentrationgel, etc. Potential energy may be stored in any manner sufficient tomaintain/restrain it until it is required. Examples include batteriesand/or capacitors, elastically, torsionally, compressively tensionedmaterials or structures, in the form of unreacted reagents, andmaterials capable of performing physical or chemical functions (e.g.,absorbents, emollients, pH buffers, enzyme inhibitors, fecesmodification agents; compressed gases, etc.).

Alternatively, an actuator 70 of the present invention may comprise aquantity of a stored material that has the capacity to perform oractivate a responsive function upon the waste, the wearer, the article,or any component or components thereof. In one embodiment, for example,the actuator 70 may release or deliver a stored material that performs aresponsive function. In this embodiment, the actuator 70 may betriggered by a threshold level of an input to discontinuously release ordeliver the stored material at a given time or may release or deliverthe material continuously. The actuator 70 may, for example, includestored lotion, skin care compositions, feces modification agents, enzymeinhibitors, pH buffers, dyes, etc. In certain preferred embodiments, thematerial may be delivered by an actuator 70 such as an expandingresilient material, a released high pressure gas, etc.

In one embodiment, as shown in FIG. 2, the article includes an actuatorthat comprises a compressed foam spacer 94 vacuum sealed under a watersoluble film 92 (e.g., a PVA film). Upon receipt of the proper signalfrom the proactive sensor, the actuator closes a switch that releases asmall amount of stored water to contact and dissolve the water solublefilm. This results in the release of the stored mechanical energy in thecompressed foam. The foam expands and forms a spacer to provide voidvolume for the incipient feces. Alternatively, the switch closure mayrelease two chemicals that combine and create a foaming system, whichmay protectively coat the skin and/or engulf the feces when excreted.Similar systems to prepare for imminent urination events are alsoincluded in the scope of this invention.

In other embodiments, the responsive system may include an actuator thatalerts the caretaker or the wearer of an impending event such as adefecation or a urination. If the responsive system alerts thecaretaker, for example, the caretaker may prepare to change the articleto minimize the amount of time that the bodily waste is in contact withthe skin of the wearer, may ensure that a bedpan or an absorbent articleis in place to contain the bodily waste when it is eliminated, or mayaid the wearer in getting to the bathroom before the elimination of thebodily waste. If the responsive system alerts the wearer, alternatively,the responsive system may act as a signaling device that alerts thewearer of an impending defecation or urination before the actual event.

Alternatively, the sensor and/or actuator may comprise a closed systemliquid transport member. A “closed system liquid transport member” or“transport member” comprises a liquid filled member having an inlet portand outlet port, which upon receipt of even a little amount of liquid atthe inlet port practically immediately releases liquid at the outletport. The liquid released from the outlet port may serve as an inputsignal to a sensor. For example, the liquid may be water, which isreleased when the transport member imbibes urine at an inlet port, whichacts to dissolve a seal to release stored mechanical energy to create afeces void space. Alternatively, the transport member may itself triggeran actuator (e.g., mix with agents to perform a chemical reaction), ormay perform at least a portion of the actuator function (e.g., thereleased water is imbibed by a super absorbent polymer arranged in aparticular geometry, which swells and forms a feces void volume). Liquidtransport through such transport members is based upon direct suctionrather than on capillarity. The liquid is transported through a regioninto which no significant quantity of air (or other gas) may enter. Thedriving force for liquid flowing through such a member can be created bya liquid sink (e.g., a capillary or osmotic absorbent structure) orsource in liquid connection with the member. Thus, a liquid transportmember must have a relatively high liquid permeability.

There are preferably at least two regions within the transport memberwith different pore sizes, namely the one or more port region(s) havingsmaller pores and the inner region having a much larger pore size. Theinner region of transport member has a permeability that is relativelyhigh compared to the permeability of a port region (a higher liquidpermeability provides less flow resistance), which can be a part of anouter/wall region circumscribing the inner/bulk region. Nonlimitingexamples of high porosity materials suitable for use as the inner regionmaterial include fibrous structures comprising polyolefin, PET,cellulose, and cellulose-based fibers, and porous, open celled foam suchas reticulated foams, cellulose sponges, polyurethane foams, and HIPEfoams. In one embodiment, the voids of the inner region are essentiallycompletely filled with an essentially incompressible fluid. The term“essentially completely” refers to the situation, where sufficient voidvolume of the inner region is filled with the liquid such that acontinuous flow path between inlet and outlet ports can be established.

The port regions of the transport member comprise materials which arepermeable for the transport liquid, but not for the ambient gas (likeair) once they are wetted with the transport liquid. Often, suchmaterials are described as membranes, which are defined as regions thatare permeable for liquid, gas or a suspension of particles in a liquidor gas. The membrane may for example comprise a microporous region toprovide liquid permeability through the capillaries. In an alternativeembodiment, the membrane may comprise a monolithic region comprising ablock-copolymer through which the liquid is transported via diffusion.Exemplary membranes for the port regions include celluloseacetatemembranes, such as also disclosed in U.S. Pat. No. 5,108,383 entitled“Membranes For Absorbent Articles” issued to White on Apr. 28, 1992, PETfilms as disclosed in EP-A-0451797, nitrocellulose membranes,cellulosenitrate membranes, PTFE membranes, polyamide membranes, andpolyester. Other suitable materials are woven polymeric meshes, such aspolyamide or polyethylene meshes as available from Verseidag inGeldern-Waldbeck, Germany, or SEFAR in Rüschlikon, Switzerland.

The actuator 70 may alternatively comprise an electrically sensitivegel. Electrically sensitive gels are polymeric gel networks that, whenat least partially swollen with water, change volume and/or geometryunder the application of an electric current or field. For example,certain partially ionized polyacrylamide gels will undergo anisotropiccontraction of about 50% under weak electric fields (e.g., 0.5 volts/cm)when immersed in acetone and water. Alternative electrically sensitivegels may undergo electrically induced bending in the presence of waterand a surfactant or may undergo an oscillating wave motion whensubjected to an oscillating electric field. It is believed that localshrinkage may be induced in a portion of the gel, e.g., one side of agel element, by concentrating positively charged surfactant molecules onthe negatively charged gel polymer in an electric field. Changing theintensity and/or the polarity of the field induces a movement in the gelas one side decreases in length (e.g., a gel formed in a strip maycurl). Electrically sensitive gels may comprise variable geometries suchas rectangular, circular, reticulated grid, etc. patterns in order toprovide a valve to release a material, allow a bodily waste to flowthrough, prevent a bodily waste from flowing through, encapsulate abodily waste, etc. as they change volume and/or geometry. Anelectrically sensitive gel formed in a strip, for example, may be bentto provide an available void space for when electrical activity in theexternal anal sphincter muscle predictive of defecation or urination isdetected. In FIGS. 6A and 6B, for example, a strip of electricallysensitive gel is shown in a circuit in which fecal moisture may bridgethe contacts 485 and allow current to flow to the electrically sensitivegel either bending or straightening the strip. Alternatively, anelectrically sensitive gel formed in a reticulated grid pattern, such asshown in FIGS. 7A, 7B and 7C, may be electrically induced to swell orshrink when an imminent urination is detected to form a valve thatallows and/or prevents urine flow to another portion of the article 20.FIG. 7A, for example, shows a circuit including a reticulated gridpattern of an electrically sensitive gel. FIGS. 7B and 7C further show amicroscopic view of the grid in a shrunk and in a swelled configuration,respectively. An exemplary material is a weakly cross-linked PAMPs gel(poly(acrylamido-2-methyl propane) sulphonic acid). This type of gel mayperform various functions such as applying or delivering a chemicalfeces treatment agent. Other exemplary electrically sensitive gels aredescribed in U.S. Pat. No. 5,100,933 issued to Tanaka on Mar. 31, 1990and WO 9202005. Alternatively, pH sensitive gels or salt concentrationsensitive gels that change volume and/or geometry at specific pH or saltconcentrations, respectively, may be used as an actuator of the presentinvention.

The actuator 70 may be disposed in and/or operatively connected to anyportion of disposable article that will allow the actuator to perform aresponsive function upon the bodily waste, the wearer, the article, or acomponent thereof. In article 20, for example, the actuator 70 may belocated in the front waist region 36, the rear waist region 38 or thecrotch region 37 of article 20, and may be integral with, disposedadjacent to or joined to a component of the chassis 22, the topsheet 24,the backsheet 26, the absorbent core 28, side panels 30, leg cuffs 32, awaist feature 34, a fastening system 40, the longitudinal 50 or end 52edges, etc. The actuator 70 may also be completely contained within thearticle such as article 20, may have a portion located in the articleand a portion located outside the article 20, or may be completelyexternal to the article 20. An actuator 70 or a portion of an actuator70 may be operatively connected to one or more sensors 60, one or morecontrollers 80, another portion of the actuator 70 or another portion ofthe article 20. Further, the actuator 70 may be integral with thearticle 20, or may be installed by the caretaker or the wearer.

The article 20 may also include a controller 80. A “controller” isdefined for the purposes of this application as a device that receivesan input from a sensor and determines if one or more actions are to betaken. The controller may receive a signal from the sensor 60 and directthe actuator 70 to perform a responsive function upon the bodily waste,the wearer, the article or a component thereof. Alternatively, theactuator 70 may receive the signal directly from the sensor 60 andperform a responsive function upon the wearer, the waste, the article ora component thereof. A controller may include materials that undergochemical or physical change, may be a chemical, mechanical or electricaldevice that processes information from a sensor, etc. For example, in anarticle having a compressed plastic foam material encapsulated andrestrained under vacuum by a moisture soluble bag, the sensor 60 maycomprise the moisture soluble bag. The physical and chemicalcharacteristics of the film, i.e., the type of polymer, the thickness,etc., that determine how much of the input must be present before thefilm will dissolve act as the controller 80 and determine the thresholdlevel of input that must be met before the controller 80 allows theactuator 70 to release stored energy to perform a responsive function.The actuator 70 is the combination of the compressed foam and the lossof vacuum, which allows release of the stored mechanical energy of thecompressed foam. In this example, the controller 80 acts as a one-timeswitch. An electrical controller 80 that receives signals from thesensor 60 such as electrical activity of muscles of the wearer, however,may receive and monitor multiple electrical signals and may repeatedlytrigger the actuator. The controller may be integral with the sensorcomponent, integral with the actuator component, or a separate componentof the system.

The controller 80 may be disposed in and/or operatively connected to anyportion of a disposable article that will allow the controller 80 toreceive a signal from the sensor 60 and to provide a signal to theactuator 70. In article 20, for example, the controller 80 may belocated in the front waist region 36, the rear waist region 38 or thecrotch region 37 of article 20, and may be integral with, disposedadjacent to or joined to the chassis 22, or a component of the topsheet24, the backsheet 26, the absorbent core 28, side panels 30, leg cuffs32, a waist feature 34, a fastening system 40, the longitudinal 50 orend 52 edges, etc. The controller 80 may be integral with the article20, or may be installed by the caretaker or the wearer. The controller80 may be completely contained within the article such as article 20,may have a portion located in the article and a portion located outsidethe article, or may be located completely outside the article 20. Acontroller 80 or a portion of a controller 80 may be operativelyconnected to one or more sensors 60, one or more actuators 70, anotherportion of the controller 80 or another portion of the article 20. Thecontroller 80, for example, may receive a signal from the sensor 60 andprovide a signal to the actuator 70, e.g., by a radio frequency (rf)transmission.

Although distinct structural elements may perform the sensor 60,actuator 70 and controller 80 functions, the sensor 60, actuator 70and/or controller 80 functions of the present invention need not beperformed by distinct structural elements. The sensor 60 and controller80 functions, for example, may be performed by the same structuralelement such as a film that dissolves in contact with a component of abodily waste. In this example, the film acts as a sensor and responds tothe input component of bodily waste. The physical and chemicalcharacteristics of the film, i.e., the type of polymer, the thickness,etc., that determine how much of the input must be present before thefilm will dissolve act as the controller and determine the thresholdlevel of input that must be met before the controller allows theactuator to release stored energy to perform a responsive function.

A “responsive system” is defined for the purposes of this application asa system that includes a sensor 60 and an actuator 70 that acts upon thebodily waste, the wearer, the article, or a component or componentsthereof when the sensor 60 detects the appropriate triggering input.Upon sensing a given input parameter, the actuator 70 effects therelease of stored energy or the release or delivery of stored materialto perform a responsive function. When the proactive sensor 60 detectsan impending event, the actuator effects the release of stored energy.By detecting an input signal prior to the impending event, a responsivesystem in the article may be triggered to prepare for the event or tosignal the caregiver or the wearer of the impending event. This allowsconstruction of articles in which the waste-management technology isinitially “hidden” or unobtrusive, but which is available at, or justbefore, the moment of need and/or in which the article may provide thecaregiver or the wearer the opportunity to prepare for an event inadvance. Regardless of the specific input, the proactive sensor 60 inthese embodiments may trigger an actuator to perform an action on thearticle, the wearer or the environment to prepare for the occurrence ofthe event or provide a signal to the caregiver that the impending eventis about to occur. For example, if an impending defecation or urinationis to be detected via the electrical activity of the external analsphincter muscles, the system is preferably triggered (i.e., theresponsive system is activated) by a signal related to the reflexivecontraction of or the relaxation of the anal sphincter. The actuator maythen perform a function such as treating the wearer's skin to prevent orminimize skin irritation; preparing a bodily waste management device byactivating a fecal void spacer; opening a valve to allow urine to flowinto a storage device; releasing an enzyme inhibitor, skin carecomposition, pH control agent, or other skin treatment aids as known inthe art; or providing an audible, tactile, or visual warning signal tothe caregiver or the wearer. If the sensor 60 comprises a sensingsystem, one actuator may be triggered by different sensors and/orsignals, or different actuators may be triggered by different sensorsand/or signals. Alternatively, one sensor and/or signal may triggermultiple actuators.

A responsive system may respond in either a “continuous” or a“discontinuous” manner. As used in this application, a “continuousresponsive system” refers to a responsive system in which the output isquantitatively dependent upon the quantity of the input, i.e.,continuously increasing quantities of the input are required to effectcontinuously increasing quantities of the output, or where the output ofthe responsive system comprises a passive release of a stored material.A super absorbent polymer placed in an absorbent core of an article, forexample, provides a continuous response in which the output isquantitatively dependent upon the quantity of the input, i.e., asincreasing quantities of liquid waste contact the super absorbentpolymer, an increasing amount of the polymer contains that liquid untilthe capacity of the polymer is exhausted. A stoichiometric chemicalreaction is another example of a system having a continuous response toincreasing output. In the reaction A+ excess B→C, for example, theamount of excess B converted to C is stoichiometrically and, therefore“continuously,” related to the amount of A available in the system. Oneexample of a continuous responsive system in which an inflatable spacerinflates to provide a void volume to store feces via a stoichiometricchemical reaction when a liquid such as urine contacts a gas evolvingmaterial, i.e., a continuous responsive system, is described in U.S.Pat. No. 5,330,459 entitled “Disposable Absorbent Article Having AnInflatable Spacer,” issued to Gary D. Lavon et al. on Jul. 19, 1994.Another example of a continuous responsive system in which a disposablearticle that improves the fit on the wearer by a liquid such as urinedissolving a film to release a leg cuff that has been held in anexpanded state is described in U.S. Pat. No. 4,246,900 entitled “DiaperIncluding Moisture-responsive Seal Means,” issued to Schroder et al. onJan. 27, 1981. A responsive system that passively releases a storedmaterial, however, generally provides a continuous response regardlessof how the material itself is released because the actual responsivefunction performed upon the bodily waste, the wearer, the article, or acomponent thereof is performed by the material, not by the release ofthe material. Thus, whether the material is released continuously inresponse to a given input, or released discontinuously at a single timewhen a threshold of a given input is detected, the responsive functionperformed by the released material is performed such that continuouslyincreasing quantities of the input are required to effect continuouslyincreasing quantities of the output until the material released isexhausted.

A “discontinuous responsive system” of the present invention, however,refers to a responsive system that has an output function that isessentially independent of the quantity of the input beyond a thresholdlevel. For example, when one or more threshold levels of a given inputare met, the responsive system may release all or a pre-designatedportion of its stored energy or deliver, i.e., actively transport, allor a pre-designated portion of its stored material to perform a specificresponsive function. In an ideal embodiment of the present invention,the output function, f(x), includes a “step” function as shown in FIG.4A. In this embodiment, the rate of change in the output with increasinglevels of input (d(output)/d(input)), i.e., the slope or firstderivative f′(x) of the output function f(x), is preferably essentiallyzero when the amount of input is above or below the threshold level. Atthe threshold level, however, the d(output)/d(input) rate of changepreferably approaches infinity. Thus, in the ideal discontinuousresponse, the limit of the function f(x−ε) as ε→0 is not equal to thelimit of the function f(x+ε) as ε→0, i.e., lim f(x−ε)≠lim f(x+ε).

ε→0ε→0

The present invention, however, recognizes that in the physical world anideal instantaneous step change at the threshold level is not necessaryand may not even be possible in many instances. In a preferredembodiment, it is only necessary that the output function have a virtualstep change with very little change in the input at or around thethreshold level of the input. Thus, the present invention contemplates adiscontinuous responsive system of the present invention having anoutput function that responds in a sufficiently discontinuous manner inthe transition region such that the output function has at least aminimum relative degree of steepness in the transition region. While notwishing to be limited to a particular method of describing or modeling adiscontinuous system, in a preferred method of determining whether agiven output function performs in a sufficiently discontinuous manner asdefined for the purposes of the present invention, the slope of theoutput curve at the inflection point is compared with the relative slopeof a line between the first and last points of the transition region.For example, FIG. 5A shows a graph of an exemplary output function, f(x)along with aligned graphs of the first, f′(x), and second, f″(x), andthird, f′″(x), derivatives of the exemplary output function. The outputfunction f(x) describes the effect of the in put (x or I) on the outputor response (R(I)). For purposes of the present invention, thetransition region is defined as the region between the relative maxima,R(I₁), and the minima, R(I₂), of the second derivative, f″(x), of theoutput function, f(x). The relative maxima, R(I₁), and the relativeminima, R(I₂), are points at which the third derivative, f′″(x), equalszero. The inflection point, I₀, is defined as the point in thetransition region at which the second derivative, f″(x), equals zero,i.e., ${\frac{^{2}R}{I^{2}}}_{I = I_{0}} = 0.$

The comparison of the slope of the output function at the inflectionpoint to the slope of a line between the first and the last points ofthe transition region can be described by the equation:${\frac{R}{I}}_{I = I_{0}} = {k{\frac{\left( {\Delta \quad R_{T}} \right)}{\left( {\Delta \quad I_{T}} \right)}.}}$

In this equation dR/dI at the inflection point is the first derivativeof the output function at that point. The term ΔI_(T) is the change inthe input to the responsive system between the first, I₁, and last, I₂,points of the transition region, i.e., I₂−I₁, and the term Δ R_(T) isthe change in the response of the output function between the first andlast points of the transition region, i.e., R(I₂)−R(I₁). The coefficientk is a proportional constant that describes the relative steepness ofthe slope of the output function at the inflection point, I₀, comparedto the slope of a line between the first and last points of thetransition region. In order that the responsive system have adiscontinuous output function, the proportional constant k must be atleast about 2.0, preferably at least about 3.0, more preferably at leastabout 5.0, even more preferably at least about 10.0, with at least about100.0 being the most preferred.

In certain embodiments, the relative degree of steepness in thetransition region of a discontinuous responsive system may also bemodeled by a transfer function of a control system having a series of aninteger number, n, first order lags with an equal time constant. Thetransfer function of the responsive system is defined for the purposesof the present invention as the ratio of the Laplace transforms of theoutput (responding variable) to the input (disturbing variable). See,e.g., Robert H. Perry & Don Green, Perry's Chemical Engineers' Handbook,Sixth Ed., Chap. 22 (McGraw Hill, Inc. 1984). As shown in FIG. 5B, therelative degree of steepness of an output function may be approximatedby the formula: KG(s) =K/(Ts+1))^(n) in which KG(s) is the transferfunction, K is a proportional element, T is the time constant of thesystem, and n is the integer number of first order time lags. In thismodel, as the number n increases, the steepness of the output functionin the transition region increases, and the model begins to approximatea discontinuous responsive system. Certain discontinuous responsivesystems of the present invention preferably may be modeled by the aboveformula when n is greater than or equal to about 25, with n beinggreater than or equal to about 50 being more preferred, and n beinggreater than or equal to about 100 being the most preferred.

As shown in FIG. 4A, a responsive system of the present invention mayinclude a single threshold level at which the responsive system mayrelease all of its stored energy to perform a specific responsivefunction or may include multiple threshold levels at which the systemmay release a pre-designated portion of its stored energy to perform oneor more specific responsive functions at each of the threshold levels.In an embodiment having a single threshold level, for example, theresponsive system may release all of its stored energy to perform theentire responsive function when that threshold level is met. In such asingle threshold embodiment, In this example, the discontinuousresponsive system includes a system that has two states such as on oroff. When a threshold quantity of an input such as bodily waste ispresent in the absorbent article, the responsive system may perform asingle responsive function upon the waste, the wearer, the article or acomponent thereof, such as enveloping the waste away from the skin ofthe user. Thus, the discontinuous responsive system may perform aone-time “switch-like” function that changes from one state to anotherin the presence of a threshold level of an input.

Alternatively, as shown in FIG. 4B, the responsive system may havemultiple threshold levels at which when each threshold level is met thesystem may release a given “quanta” of energy or deliver a givenquantity of material to perform a specific responsive function. In thisembodiment, when each threshold level is met, a portion of the entireresponsive function may be performed and/or different independentresponsive functions may be performed in response to different thresholdlevels being met. For example, a responsive system may monitor a fecalenzyme and when each threshold enzyme level is met may deliver an equalor unequal quantity of enzyme inhibitor(s) or lotion, or deliver a pHbuffer at the first threshold level and perform another responsivefunction such as delivering a quantity of enzyme inhibitor(s) at thesecond threshold level. In each transition region, the responsive systemresponds essentially the same as the transition region in the singlethreshold embodiment described above.

In addition, a responsive system may monitor multiple inputs such asmoisture and/or one or more fecal enzymes and perform one or moreresponsive functions when the threshold levels of the different inputsare met or may perform one responsive function only when two or more ofthe threshold levels of the different inputs are met. Thus, a controllermay monitor multiple different inputs and perform a different responsivefunction when the threshold level of the different inputs are met.Alternatively, the controller may perform a logic OR-gate type functionsuch that a responsive function may be performed when one or morethreshold levels of the multiple inputs are met. The controller may alsoperform a logic AND-gate type function such that a responsive functionmay be performed when each threshold level of two or more differentinputs is met.

The responsive system may also comprise a “closed loop” or an “openloop” system. A “closed loop” system, which is also referred to as a“feedback control loop” system, includes distinct sensor 60 and actuator70 components and performs a responsive function upon the input. In somepreferred embodiments, the system may also use a detection or ameasurement of an element or a parameter of the output condition as atleast one trigger of the responsive function that is performed upon theinput. The output condition may be the state of the input conditionafter the actuator 70 has had the opportunity to perform a responsivefunction on the input condition. For example, if the sensor 60 ismonitoring the hydration level of the skin and the hydration levelreaches a threshold level, i.e., the output condition of the responsivesystem, the responsive system may release a predetermined quantity of adesiccant to bring the hydration of the skin back to the desired targethydration or hydration range or may release a desiccant until thehydration returns to the target hydration or the hydration range. Anabsorbent material such as a super absorbent polymer that continuallyabsorbs a liquid input until the liquid has all been absorbed or thecapacity of the polymer has been reached, however, is not considered tocomprise a closed loop system because the absorbent material does nothave distinct sensor 60 and actuator 70 components. The responsivefunction may be performed when the output condition reaches a thresholdlevel, or may be performed only when the output condition and one ormore other conditions are met. Acting upon the input may include actingupon the element sensed, e.g., sensing pH and acting upon the pH, or mayinclude acting upon a composition of which the element sensed is anintegral component, e.g., sensing a fecal enzyme or fecal moisture andacting upon feces. As described above, a feedback control loop systemincludes at least two distinct components: the sensor 60 and theactuator 70. The sensor 60 detects an event, or a parameter associatedwith that event. The actuator 70 receives a signal and performs aresponsive function on the input condition detected by the sensor 60.The feedback control loop may further include a controller 80. In thiscase, the sensor 60 may provide a signal to the controller 80, and thecontroller 80 may direct the actuator 70 to perform a responsivefunction upon the input condition. The controller 80 may be a separatecomponent of the responsive system or the controller function may beperformed by the sensor 60 and/or the actuator 70.

A preferred embodiment of a closed loop control system of the presentinvention comprises an electrical sensor capable of detecting changes inthe magnitude of electrical activity of sphincter muscles, particularlythe external anal sphincter, related to imminent release or thepotential for release of bodily waste and a means to deliver anelectrical impulse (or electrical stimulation) as required to theperianal skin of the wearer to induce a temporary contraction of thesphincter muscle to function as a continence aid. (This process may bealternatively referred to as dynamic graciloplasty nerve stimulation inthe medical literature.) For the purpose of this invention, theelectrical activity herein referred to as the electrical activity of theexternal anal sphincter may additionally include electrical activityfrom other pelvic floor muscles associated with the external analsphincter. Optionally, a visible, audible, and/or tactile (i.e.,vibrating) signal is delivered to the wearer and/or caregiver, alertingthem of the potential for waste elimination. This approach may also beapplied to the external urethral sphincter. The electrical impulse mayconsist of one or more pulses of electricity or may be a continuousimpulse. While the maximum strength of the electrical impulse may be ashigh as about 35 volts, the electrical impulse preferably has a voltagein the range of about 0.05 to about 5 Volts and more preferably in therange of about 0.3 to about 1 Volt. Preferably, the electrical impulsecurrent is in the range of about 0.1 to about 100 mA. Preferably, thestimulation frequency is in the range of about 10 to about 100 Hz, morepreferably in the range of about 20 to about 80 Hz, and even morepreferably in the range of about 60 to about 80 Hz. If the impulse is apulse (one or a multiplicity of pulses), the duration of each pulse ispreferably in the range of about 0.1 to about 5 ms and more preferablyin the range of about 0.5 to about 1 ms. In certain embodiments wherethe impulse comprises a multiplicity of pulses, the entire set ofpulses, or “pulse train”, may have a duration of about 0.1 second toabout 15 seconds with an interval between pulse trains of between about1 second and about 60 seconds. Preferably, the electrical stimulationvoltage, frequency, the number and frequency of pulses in a pulse train,and the number and duration of and spacing between pulse trains may bemodified and/or controlled by the wearer or the caregiver. Anyelectrical circuit as known in the art capable of meeting theseparameters may be used to deliver or control the electrical stimulationto the external anal sphincter or other body location. For example, a 3volt watch battery with a pulse generating system may operativelyconnected with a proactive sensor, such as an EMG surface electrode asdescribed herein, and be used to deliver one or more electrical impulsesto the wearer's skin in the perianal region. One exemplary electricalstimulation device is the Prosper e.i.s. 5000 system available from theDr. Rowedder Biomedizinische Geraete in Muehbrook, Germany. This devicemay be alternatively used with an adhesive EMG surface electrode asdescribed herein.

In alternative embodiments of stimulation (i.e., contraction) of theexternal sphincter muscles as a continence aid, the signal from thesensor may be directed to another site on the wearer's body to elicitthe anorectal reflex. For example, the sensor may trigger an electricalor mechanical stimulation of the perineal skin, the skin at the back ofthe wearer's knee, the sole of the foot, or any other site that resultsin the expression of the anorectal reflex.

The feedback control loop may be “non-modulating” or “modulating.” In a“non-modulating” feedback control loop responsive system the responsivesystem acts as a one-time switch in which the actuator performs aresponsive function on the input when the threshold level of the outputcondition is met. For example, the sensor 60 may detect a specificmicroorganism, and the actuator 70 may signal the caretaker of apotential incipient infection. In this example, the actuator 70 actsupon the input detected by the sensor 60. If the sensor 60 detectselectrical signals in the external anal sphincter of the wearer topredict an imminent defecation and the actuator 70 releases a compressedfoam material to create a shaped void of sufficient volume to containfeces, however, the actuator 70 acts upon something other than the inputdetected by the sensor 60, i.e., acts upon the feces instead of theelectrical activity in the sphincter muscles and is therefore not afeedback control loop. A “modulating” feedback control loop, however,includes a sensor 60, an actuator 70 and a controller 80. In amodulating feedback control loop, the output condition is monitoredconstantly or repeatedly, and the controller 80 directs the actuator toperform a responsive function on the input in order to maintain theoutput condition at a desired set point or within a desired range. Amodulating responsive system may constantly or repeatedly measuresphincter muscle electrical activity and send a signal to the sphinctermuscles to keep the anal sphincter closed for a desired period of timeto provide a feedback control loop responsive system.

An “open loop” system, however, is a system that responds to the inputto perform a responsive function without using feedback, i.e., theoutput has no effect upon the sensed input entering the system. An openloop system may include a responsive system that has a single devicethat performs the functions of both the sensor 60 and the actuator 70 ormay have distinct sensor 60 and actuator 70 components in which theactuator acts upon something other than the input. A super absorbentpolymer placed in an absorbent core of a disposable absorbent article,for example, provides an open loop response because the polymer onlyincludes a single device that performs the functions of the sensor 60and actuator 70. Alternatively, an open loop responsive system mayinclude a sensor 60 that detects bodily waste or a component of thatbodily waste, and an actuator 70 that performs a responsive function ina continuous or a discontinuous manner on something other than the inputdetected by the sensor 60. As above, for example, the sensor 60 maydetect sphincter muscle electrical activity, and the actuator 70 maycapture or store feces.

A block diagram of an exemplary open loop responsive system having asensor 60 and an actuator 70 is shown in FIG. 6A. A block diagram of analternative open loop responsive system including a sensor 60, anactuator 70 and a controller 80 is shown in FIG. 6C. A block diagram ofan exemplary closed loop responsive system having a sensor 60 and anactuator 70 is shown in FIG. 6B. A block diagram of an alternativeclosed loop responsive system including a sensor 60, an actuator 70 anda controller 80 is shown in FIG. 6D.

Other responsive systems are described in U.S. patent application Ser.Nos. 09/106,424 entitled “Disposable Article Having A DiscontinuousResponsive System” filed on Jun. 29, 1998 (P&G Case Number 7197);09/107,563 entitled “Disposable Article Having A Responsive SystemIncluding A Feedback Control Loop” filed on Jun. 29, 1998 (P&G CaseNumber 7198); and 09/106,225 entitled “Disposable Article Having AResponsive System Including A Mechanical Actuator” filed on Jun. 29,1998 (P&G Case Number 7199), each of which is incorporated herein byreference.

An example of a diaper 20 of the present invention including a proactivesensor is shown in FIG. 1. In this embodiment, a skin contact sensorsystem comprises an electrical sensor 60 that includes three electrodes64, 65 and 66. An electrical sensor 60 of the present invention mayinclude two or more electrodes. In one embodiment, electrodes 64 and 65may be active and electrode 66 may be a reference electrode. This allowsfor a bimodal electrical pickup. The skin contact sensor system may bereleasably secured to the skin of the wearer in order to receiveelectrical signals from a muscle or muscle group of the wearer. Forexample, the skin contact sensor may be placed as close as possible tothe anus of the wearer so that the probe may detect signals from theexternal anal sphincter muscle, which is anatomically near the skin atthe point of the anal orifice. If the sensor is not self-adhesive, anelectroconductive, adhesive gel may be placed on the electrode of theskin contact probe before it is placed on the skin. In this embodiment,the skin contact sensors may be placed on the wearer by the caretaker,or may be integral with the article such that they are automaticallyaligned and attached to the wearer's skin near the anal perimeter whenthe article is placed on the wearer. A 7 mm adhesive disposable surfaceelectrode manufactured by Dantec Medical A/S of Skovlunde, Denmark,which may be connected to a Dantec EMG (Type 14 D11) receiver unit, forexample, is believed to be useful for the present invention. In thisexample, the Dantec EMG unit may be set, for example, at a time base of20 msec/division resulting in a screen sweep time of 0.2 seconds. Thegain amplifier may be set at 20 μV/division. A proactive sensor in thisembodiment may vary in size and manufacture and may optionally beintegral with the body of the article. The unit that receives the signalfrom the sensor(s) may be separate from the article or may be integralwith the article. If the receiver unit is separate from the article(i.e., a telemetry based system), the article may additionally comprisea transmitter to transmit the signal to the receiver. This may beaccomplished, for example, via an infrared (IR) or radiofrequency (RF)telemetry device. The settings for the sensor, transmitter (ifrequired), and receiver may vary according to the specific type ofsignal, sensor embodiment, and function to be performed.

The surface electrodes 64, 65 and 66 of the skin contact sensor systemin the above embodiment measure electrical signals in a muscle fiber ora group of muscle fibers. If the electrodes measure the electricalactivity of a group of muscle fibers, the total potential changeinvolves a greater mixture of frequencies. Preferably, the skin contactsensor or sensor system is capable of detecting electrical activitythroughout a frequency range including from about 5 Hz to about 500 Hz,and more preferably including from about 10 to about 350 Hz. Preferably,the electrodes utilize two active electrodes 64 and 65 and one referenceelectrode 66 for a bimodal electrical pickup. The electrical activitymeasured by the surface electrodes includes a combination of EMGsignals, other physiologic signals present on the skin surface such asEKG and electrodermal activity, and environmental artifacts such as 60Hz from electronic equipment or radio frequency interference. Whenbimodal electrodes are used in combination with a differentialamplifier, only those signals which are not detected in common by thetwo active electrodes are allowed to pass. Because a substantial portionof the common mode signals picked up by the electrodes are not EMGsignals, it may be advantageous to reject signals common to both activeelectrodes. This common mode rejection provides a cleaner, more discretesignal from the sensor.

In alternative embodiments, the electrical skin contact sensor of thepresent invention may be any other commercially available EKG(electrocardiogram) or EMG (electromyogram) electrode and/or measuringsystem. For example, the MyoTrace 200, available from Noraxon U.S.A.,Inc. of Scottsdale, Ariz., comprises a wideband electrode capable ofsensing muscle electrical activity in the 16 Hz to 500 Hz range (this isappropriate for the slow-twitch muscles of the pelvic floor). Anothercommercially available EMG sensing system is the MyoSense systemavailable from MIE Medical research Ltd., of Leeds, U.K. Other suitableadhesive surface electrodes include electrodes available from MedicotestA/S of Olstykke, Denmark as M-00-S, N-00-S, M-00-A/F, BS 3400, BS 3500,BR, and BRS, as well as electrodes available from Multi Bio Sensor, Inc.of El Paso, Tex., as 3ST3, 3SG3-N, and 2DT2. Other suitable electricalsensors are disclosed in U.S. Pat. Nos. 5,785,040; 5,727,549; 5,337,748;5,203,330; 5,255,677, all of which are incorporated herein by reference.The electrodes of the present invention preferably comprise anelectrically conductive adhesive to maintain uninterrupted contact withthe wearer's skin.

In additional alternative embodiments of the present invention, thetelemetry system may be any commercially available EMG or EKG telemetrysystem. One suitable telemetry system is available from Noraxon U.S.A.,Inc. as the Telemyo system, comprising a battery-operated wearabletransmitter. Another suitable telemetry system is available from MIEMedical Research Ltd. as the MT8 Telemetry System. Another suitabletelemetry system is disclosed in U.S. Pat. No. 5,704,351.

For embodiments in which an imminent defecation or urination is to bedetected via the electrical activity of the external anal sphinctermuscles, the proactive sensor 60 may respond to a signal related toeither the reflexive contraction of or the relaxation of the externalanal sphincter. Certain preferred embodiments of the present inventiondetect the contraction of the external anal sphincter as a signal ofimminent or potential defecation. In continent adults and older childrenand babies, the rapid filling of the rectum with feces from the sigmoidjunction (i.e., the lower region of the colon) causes the external analsphincter to reflexively (i.e., involuntarily) contract. This reflex isreferred to as the anorectal reflex. A sharp increase in the externalanal sphincter muscle activity accompanies the contraction of theexternal anal sphincter and is detectable as an EMG signal via thesensors of the present invention. This reflex is absent in the newbornhuman infant and generally begins to develop after about one year ofage. Therefore, embodiments of the present invention intended to detectincreased external anal sphincter activity as a precursor of defecationmay be generally more applicable to older babies (older than about 1year of age). The increase in external anal sphincter electricalactivity that signals rectal filling is preferably at least about 2times the basal external anal sphincter muscle activity, but may be atleast about 3 times the basal activity, at least about 5 times the basalactivity or more.

In other preferred embodiments, the sensor detects sharp decreases in,or the absence of, the electrical activity of the external analsphincter. These decreases occur when the external anal sphincterrelaxes to open the rectal neck just prior to, or during, defecation.Generally, the electrical activity of the external anal sphincter musclewill drop sharply for at least several seconds as the muscles relax. Theactivity is at or close to zero immediately preceding and during theelimination process. In these embodiments, a sensor 60 may be triggeredby precipitous drops in muscle electrical activity, preferably drops ofgreater than or equal to about 50%. More preferably, the sensor 60 maybe triggered by drops of greater than or equal to about 75%, or equal toabout 95%.

Since muscular electrical activity is typically “noisy”, an averagedvalue of the amplitude (i.e., absolute value of the signal) should beused for comparison of the external anal sphincter activity undervarious conditions (e.g., basal state and stimulated conditions). FIG.10a is a graphical representation (Electrical Activity of Anal Sphincterv. Time) of a sharp increase in the external anal sphincter electricalactivity related to the extension of the rectum (i.e., for a normaladult) that is useful as a signal of imminent or potential defecation.The figure shows a basal sphincter muscle electrical activity level (a)followed by rectal filing which results in an increase in the magnitudeof electrical activity of the sphincter muscle related to the anorectalreflex (b). FIG. 10b is a graphical representation of a sharp decreasein the external anal sphincter electrical activity related to imminentor current defecation. The sphincter muscle activity during defecation(c) is shown between the anorectal reflex electrical activity (b) andthe basal electrical activity (a), which is typical.

Preferably, the target or “trigger” level of muscle electrical activityincrease or decrease that results in the signaling of the wearer orcaregiver or the application of an electrical stimulus may be varied orcontrolled by the wearer or caregiver based on differences betweenindividual wearers. In certain embodiments, one or more sequences ofelectrical stimuli to be delivered to a portion of the wearer's anatomy(e.g., the perianal skin) based on the particular detected muscleelectrical signal may be pre-programmed into a controller operativelyassociated with the sensor/actuator (i.e., stimulation device).

While particular embodiments and/or individual features of the presentinvention have been illustrated and described, it would be obvious tothose skilled in the art that various other changes and modificationscan be made without departing from the spirit and scope of theinvention. Further, it should be apparent that all combinations of suchembodiments and features are possible and can result in preferredexecutions of the invention. Therefore, the appended claims are intendedto cover all such changes and modifications that are within the scope ofthis invention. Also, although the present invention is illustrated anddescribed primarily with respect to a disposable diaper, the presentinvention is not limited to this embodiment. The present invention mayalso be used, for example, in articles that are applied directly to awearer (e.g., to the perianal or perineal regions of the wearer) priorto the application of a disposable diaper or in place of a disposablediaper, in a pull-on diaper, a diaper insert, a sanitary napkin, atampon, etc. It is therefore intended to cover in the appended claimsall such changes and modifications that are within the scope of thisinvention.

What is claimed is:
 1. A disposable article to be fitted to a wearerhaving a sphincter muscle, the sphincter muscle having a basalelectrical activity, the disposable article comprising: a sensoroperatively connected to the article, the sensor being adapted to detectelectrical activity of the wearer's sphincter muscle that correlates toan impending elimination of bodily waste and to provide a signal to thewearer, a caregiver or an element of the article.
 2. The disposablearticle of claim 1 wherein the sensor can detect the electrical activityof the wearer's sphincter muscle in the range of about 5 Hz to about 500Hz.
 3. The disposable article of claim 1 wherein the sensor includes anadhesive surface electrode which can be adhered to the wearer's skin. 4.The disposable article of claim 1 wherein the sensor detects an increasein the electrical activity of the wearer's sphincter muscle activity ofat least about two times the basal electrical activity of the sphinctermuscle.
 5. The disposable article of claim 1 wherein the sensor detectsan increase in the electrical activity of the wearer's sphincter muscleactivity of at least about three times the basal electrical activity ofthe sphincter muscle.
 6. The disposable article of claim 1 wherein thesensor detects an increase in the electrical activity of the wearer'ssphincter muscle activity of at least about five times the basalelectrical activity of the sphincter muscle.
 7. The disposable articleof claim 1 wherein the sensor detects a decrease in the electricalactivity of the wearer's sphincter muscle of at least about 50% from thebasal electrical activity.
 8. The disposable article of claim 1 whereinthe sensor detects a decrease in the electrical activity of the wearer'ssphincter muscle of at least about 75% from the basal electricalactivity.
 9. The disposable article of claim 1 wherein the sensordetects a decrease in the electrical activity of the wearer's sphinctermuscle of at least about 95% from the basal electrical activity.
 10. Thedisposable absorbent article of claim 1 further comprising: (a) atopsheet; (b) a backsheet having a body-facing surface and agarment-facing surface, the backsheet being joined to at least a portionof the topsheet; (c) an absorbent core disposed between the topsheet andthe backsheet.
 11. The disposable article of claim 10 further comprisinga waste bag operatively associated with the topsheet, the waste bagdisposed so as to receive at least a portion of the bodily waste of thewearer.
 12. The disposable article of claim 1 wherein the disposablearticle is a waste receiving article which is adhesively applied to thewearer to collect feces or urine from an artificial stoma, the anus, orurethra.
 13. The disposable article of claim 1 wherein the wearer'ssphincter muscle is an external anal sphincter muscle or an externalurethral muscle.
 14. A disposable article to be fitted to a wearerhaving an sphincter muscle, the sphincter muscle having a basalelectrical activity, the disposable article comprising: a sensoroperatively connected to the article, the sensor being adapted to detectan input that correlates to an impending elimination of bodily waste andprovide a signal to a portion of the wearer's anatomy, the signalresulting in temporary contraction of the wearer's sphincter muscle. 15.The disposable article of claim 14 wherein the signal is an electricalstimulation of the perianal skin.
 16. The disposable article of claim 15wherein the electrical stimulation has voltage in the range of about 0.1Volts to about 5 Volts.
 17. The disposable article of claim 15 whereinthe electrical stimulation has current between about 0.1 mA to about 100mA.
 18. The disposable article of claim 15 wherein the electricalstimulation has frequency of between about 10 Hz to about 100 Hz. 19.The disposable article of claim 15 wherein the electrical stimulationhas frequency of between about 60 Hz to about 80 Hz.
 20. The disposablearticle of claim 15 wherein the electrical stimulation comprises one ormore pulses.
 21. The disposable article of claim 20 wherein the pulseshave duration between about 0.1 ms to about 5 ms.
 22. The disposablearticle of claim 20 wherein the pulses have duration between about 0.5ms to about 1 ms.
 23. The disposable article of claim 20, wherein theelectrical stimulation comprises a pulse train having a duration ofabout 0.1 to about 15 seconds.
 24. The disposable article of claim 14,wherein the sensor provides a signal to the caretaker.
 25. Thedisposable article of claim 14, wherein the sensor provides a signal tothe wearer.
 26. The disposable article of claim 14 wherein the sensorcan detect the electrical activity of the wearer's sphincter muscle. 27.The disposable article of claim 14 wherein the sensor can detect theelectrical activity of the wearer's sphincter muscle in the range ofabout 5 Hz to about 500 Hz.
 28. The disposable article of claim 14wherein the sensor detects an increase in the electrical activity of thewearer's sphincter muscle activity of at least about two times the basalelectrical activity of the sphincter muscle.
 29. The disposable articleof claim 14 wherein the sensor detects an increase in the electricalactivity of the wearer's sphincter muscle activity of at least aboutthree times the basal electrical activity of the sphincter muscle. 30.The disposable article of claim 14 wherein the sensor detects anincrease in the electrical activity of the wearer's sphincter muscleactivity of at least about five times the basal electrical activity ofthe sphincter muscle.
 31. The disposable article of claim 14 wherein thesensor detects a decrease in the electrical activity of the wearer'ssphincter muscle of at least about 50% from the basal electricalactivity.
 32. The disposable article of claim 14 wherein the sensordetects a decrease in the electrical activity of the wearer's sphinctermuscle of at least about 75% from the basal electrical activity.
 33. Thedisposable article of claim 14 wherein the sensor detects a decrease inthe electrical activity of the wearer's sphincter muscle of at leastabout 95% from the basal electrical activity.
 34. The disposable articleof claim 14 further comprising: (a) a topsheet; (b) a backsheet having abody-facing surface and a garment-facing surface, the backsheet beingjoined to at least a portion of the topsheet; (c) an absorbent coredisposed between the topsheet and the backsheet.
 35. The disposablearticle of claim 34 further comprising a waste bag operativelyassociated with the topsheet, the waste bag disposed so as to receive atleast a portion of the bodily waste of the wearer.
 36. The disposablearticle of claim 14 wherein the disposable article is a waste receivingarticle which is adhesively applied to the wearer to collect feces orurine from an artificial stoma, the anus, or urethra.
 37. The disposablearticle of claim 14 wherein the wearer's sphincter muscle is an externalanal sphincter muscle or an external urethral muscle.